Medical interconnects: from the design to the complete solution

8 Apr 2016

Because the medical market is essential for Axon', the company will be present at MedtecEurope in Stuttgart from 12th to 14th April at MTI-Expo in Conventry in the UK from 20th to 21st April. From the design to ready-to-plug cable assemblies, Axon' offers complete solutions which take into account the regulatory constraints fo the medical devices.

Regulatory constraints

Certified to ISO 13485 since January 2011, Axon’ Cable is particularly well versed in the statutory context of the medical devices. So, from the designing of cable assemblies, harnesses, mini systems (complete interconnects integrating cabling solution and mechanical elements), Axon’ teams take into account the different standards that are required in the manufacturing of medical products. For example standards such as CEI60601, IS010993, ISO 11607 (Packaging of medical devices), EN ISO 11737 (Sterilisation of MD), 90/385/CEE (implantable active MD), 93/42/CEE.

First step of the manufacturing: designing

Define as best constraints and requirements on the product is a key step in the design. A study of the product life cycle is done with the customer in order to highlight the potential risks related to handlings of the cable assembly by the medical staff and patient. Risks related to sterilisation protocol (ETO and autoclave) are also taken into account. During the designing step, Axon’ has tools that are able to characterise EMI performances of products, or validate upstream the flex-life of cables. Engineers also use modelling software (Inventor / CATIA) to design different mechanical parts. They can define the routing, that is to say, the way where the cable must pass through the integration of the products in the customer’s system. In order to validate the recommended solution, Axon’ can propose functional prototypes to validate the design of the links.

Internally equipped with 3D-printers and digital micro milling machine, Axon’ can realise – in short time – forms for overmoulding, realise a model to validate a design of connector or manufacture a representative model of the customer’s integration environment.

Cables: from the conductor to the jacket

Flexibility, resistance, miniaturisation, EMI performances, sterilisation and biocompatibility (ISO10993, USP class 6) these are the numerous constraints that cables need to meet in the medical market. To satisfy all the requirements, Axon’ has a large expertise in technical fields. The company has integrated the manufacture of conductors and can offer flexible and long life resistant wires and cables. Axon’ can draw, that is to say reduce the diameter of the conductors up to 15 µm. Another decisive know-how in the medical market: wires and cables insulation. Since more than 50 years, the company has manufactured wires and cables insulated with PFA, FEP, PTFE and Celloflon® (expanded PTFE, patented by Axon’), coaxial cables including miniature coaxial cables (Picocoax®), used in sensors for example. Since its creation, Axon’ has manufactured PTFE tubes which allow the transfer of fluids or liquids. It is necessary that medical devices are not disrupted by EMI (electromagnetic interferences). Links are then shielded in order to ensure the best possible protection.

Biocompatibility and sterilisation

Whether it is used for endoscopic equipments or ambulatory, cables and cable assemblies can be in contact with patients’ skin. Outer jacket of Axon’ interconnections are manufactured with biocompatible materials (ISO10993 §5 and 10, USP class VI). In order to avoid the propagation of nosocomial diseases, cables jackets have to withstand the constraints of chemical sterilisation. As for silicone insulated cables, they are designed to withstand the constraints of sterilisation with autoclave.

All-in-one solutions

Axon’ can offer complete solutions integrating cables, connectors, overmoulding, mechanical pieces and components. Ranging through from the preparation of the wires, to the connection, the shielding and the finishing of the cables assemblies with overmoulding, Axon’ supplies all-in-one solutions. For instance, Axon’ manufactures, for one of its customers, silicone insulated cable assemblies which can be sterilized in autoclave and integrate mechanical assembling of motors. These motors interface on the customer’s system. Once delivered, the customer just has to connect the cable assembly onto the medical device.

To produce clean

Ranging from prototypes, large-scale production or small series, Axon’ can realise connections on its site in Montmirail, France but also on its Latvian site. Because it can be essential to limit at most the contamination of these links, Axon’ equipped with an ISO 7 clean room (with ISO 5 laminar flows). This is the ideal place to manufacture silicone insulated cable assemblies to be implanted for long term or to ensure an initial low contamination of the links. Microbiological controls are regularly made during the different steps of the manufacturing directly onto the product or on the operator’s gloves.